Harman MS-10SD2 Suggested Enclosures, Enclosures Internal Volume, Calculation Instructions

2.You must use both coils of a dual voice-coil woofer connected either in series or in parallel.

3.Most amplifiers deliver exactly the same amount of power bridged into a 4-ohm load as they do running a 2-ohm stereo load.

English

SUGGESTED ENCLOSURES

MODELS SEALED BOX	VENTED BOX
Internal Volume	Internal Volume Qty.	Duct(s) Diameter x Length

To design a subwoofer system that maximizes available amplifier power, keep the following rules in mind:

1.The total system impedance of woofers in parallel can be calculated using this formula:

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MS-10SD2	0.78 ft3 (22L)
MS-10SD4	0.78 ft3	(22L)
MS-12SD2	0.95 ft3	(27L)
MS-12SD4	0.95 ft3	(27L)
MS-15SD2	1.27 ft3	(36L)

1.13 ft3 (32L)		1	2.95 in x 9.84 in (7.5cm x 25cm)
1.13 ft3	(32L)	1	2.95 in x 9.84 in (7.5cm x 25cm)
1.7 ft3	(48L)	1	3.94 in x 8.66 in (10cm x 22cm)
1.7 ft3	(48L)	1	3.94 in x 8.66 in (10cm x 22cm)
2.12 ft3	(60L)	2	3.94 in x 14.96 in (10cm x 38cm)

Impedance =
	1		+	1		+	1		...
	w	1		w	2		w	3

where w is the nominal impedance of the woofer.

2.The total system impedance of voice coils (or woofers) in series can be calculated using this formula:

Impedance = w1 + w2 + w3 ...

The diagrams below show parallel and series speaker connections.

Figure 1. Parallel connection Figure 2. Series connection

–The suggested enclosure volumes are related to only one speaker, including woofer and duct(s) displaced volume.

–For enclosures with more than one speaker, it is necessary to multiply the suggested volume and duct(s) by the quantity of speakers.

ENCLOSURES INTERNAL VOLUME

CALCULATION INSTRUCTIONS

RECTANGULAR BOX		TRAPEZOID RECTANGULAR BOX
Internal Volume =	A x B x C		A x B x (	C + D	)
	1000	Internal Volume =		2
			1000

– A, B and C are internal dimensions.

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